Most golf putters are provided with a smooth ball-striking face, with greater or lesser degree of loft in order to control the distance and direction that a struck golf ball travels. Generally, a golf ball struck by a lofted putter initially travels slightly upwards while spinning backwards, which causes the golf ball to skid or slide across the putting surface for a short distance after impact. Friction between the ball and the putting surface results in a forward moment opposing the backspin which eventually imparts a forward roll to the ball. When a golf ball is rolling forwards rather than skidding or sliding over the putting surface, the ball is less influenced by surface irregularities and the rotational inertia of the ball will cause it to have more of a tendency to continue in the true direction of the putting stroke. Thus, it is desirable to get a ball “rolling” as early after impact as possible.
Various attempts have been made to provide an improved putter that aids in imparting forward roll or topspin to a golf ball. For example, it is known to provide the front face of a putter with upwardly angled, V-shaped projections that are elongated in the direction from the heel to the toe of the putter. The sharp edges of the projections purportedly enhance friction between the putter face and the ball, creating a gripping effect as the putter comes in contact with the ball, which promotes the transfer of topspin to the ball.
There is also a demand for putters that transfer sufficient momentum to the golf ball while providing an improved “feel” for the player. The “feel” of a club generally relates to the sensory feedback that the player receives when the club head strikes the golf ball. In other words, an improved “feel” gives the player a greater sense that the putter head is an extension of the player's hands and the perception that the player is more able to guide the ball along the desired path to the hole. The feel of the putter head is primarily a function of the spring constant (k) of the putter face. The spring constant is generally determined by the Young's modulus of the material, as well as the contact area (i.e., the amount of surface area on the putter face that actually contacts the ball during the putting stroke).
When projections have been used in connection with putters, the projections unfortunately have lacked the proper structure to effectively improve the feel and control of the putter. For example, the projections typically have sharp tips, which collectively form the contact face of the putter. Because the contact area is relatively small, the ball trajectory tends to be less controllable. The lack of sufficient contact area can also result in inconsistencies between putting strokes, since the impact of the club on the ball varies significantly depending upon the location and the angle of the putter face relative to the ball. Additionally, the sharp ends of the projections increase the friction between the club face and the ball, which can result in the club conferring too much spin to the ball so that ball trajectories can be unusual and unpredictable.
To improve the feel of the putter, golf club manufacturers have designed putter heads with soft plastic inserts that are mounted on the face of the putter head. The plastic inserts are mainly directed toward improving the feel of the putter through the use of low modulus material. The plastic inserts generally have a low Young's modulus to improve the feel of the putter, but unfortunately also present certain disadvantages. In particular, plastic inserts have a tendency to lower the sound when the club impacts the ball which causes a lack of acoustic feedback to the player. Additionally, such inserts do not promote the transfer of topspin to the ball to improve control.
Accordingly, there is a need for a golf putter that promotes the transfer of topspin to the ball to improve accuracy while providing improved feel.